Isolation and characterization of a Geobacillus thermoleovorans strain from an ultra-deep South African gold mine

• Published in: Systematic and applied microbiology Vol. 30; no. 2; pp. 152 - 164
• Main Authors: DeFlaun, M.F., Fredrickson, J.K, Dong, H., Pfiffner, S.M., Onstott, T.C., Balkwill, D.L., Streger, S.H., Stackebrandt, E., Knoessen, S., van Heerden, E.
• Format: Journal Article
• Language: English
• Published: Jena Elsevier GmbH 01-03-2007; Elsevier
• Subjects: Bacillaceae - classification; Bacillaceae - cytology; Bacillaceae - isolation & purification; Bacillaceae - physiology; Bacterial Typing Techniques; Bacteriology; Biological and medical sciences; Cellobiose - metabolism; Deep subsurface bacteria; DNA, Bacterial - chemistry; DNA, Bacterial - genetics; Environmental Microbiology; Extremophiles; Fatty Acids - analysis; Fatty Acids - isolation & purification; Flagella; Freshwater; Fundamental and applied biological sciences. Psychology; Genes, rRNA; Geobacillus; Geobacillus thermoleovorans; Gold; Hot Temperature; Hydrocarbons - metabolism; Hydrogen-Ion Concentration; Lactic Acid - metabolism; Lipase; Microbiology; Microscopy, Electron, Transmission; Mining; Miscellaneous; Molecular Sequence Data; Nitrates - metabolism; Phylogeny; RNA, Bacterial - genetics; RNA, Ribosomal, 16S - genetics; Sequence Homology, Nucleic Acid; South Africa; Spores, Bacterial; Thermophilic bacilli; South Africa; Africa; Thermophilic bacilli; Lipase; Geobacillus thermoleovorans; Deep subsurface bacteria; Extremophiles; Characterization; Mine; Bacteria; Isolation; Thermophily; Extreme environment; Strain
• ISSN: 0723-2020; 1618-0984
• DOI: 10.1016/j.syapm.2006.04.003

A thermophilic facultative bacterial isolate was recovered from 3.2
km depth in a gold mine in South Africa. This isolate, designated GE-7, was cultivated from pH 8.0, 50
°C water from a dripping fracture near the top of an exploration tunnel. GE-7 grows optimally at 65
°C and pH 6.5 on a wide range of carbon substrates including cellobiose, hydrocarbons and lactate. In addition to O
2, GE-7 also utilizes nitrate as an electron acceptor. GE-7 is a long rod-shaped bacterium (4–6
μm long×0.5
μm wide) with terminal endospores and flagella. Phylogenetic analysis of GE-7 16S rDNA sequence revealed high sequence similarity with
G. thermoleovorans DSM 5366
T (99.6%), however, certain phenotypic characteristics of GE-7 were distinct from this and other previously described strains of
G. thermoleovorans.